Anti-hypertensive treatment during pregnancy – a review

This study investigated the effects of drugs to treat hypertension (anti-hypertensives, AHTs) in pregnancy.

They found that AHTs may prevent severe hypertension but the effect on other outcomes is unclear.   

Hypertension or high blood pressure (BP) is a common condition during pregnancy. In most cases, women will have mild to moderate hypertension (MMH). To manage hypertension, women may be prescribed drugs to reduce BP. These drugs are called anti-hypertensives (AHTs). 

Managing BP in pregnancy is important to prevent conditions such as pre-eclampsia (PE). PE is a serious condition that includes severe high BP. Some doctors treat MMH to reduce the risk of PE later in pregnancy. It is unclear if AHTs are useful in treating MMH in pregnancy.

This study reviewed 46 reports including 4282 pregnant women. In these trials, women had MMH and were treated with different AHTs. The authors analyzed and compared the results from each study. They analyzed the risk of severe hypertension, proteinuria (protein in the urine, PU) and PE in mothers. They also analyzed the risk of death, low birth weight, and preterm birth. 

AHT treatment reduced the risk of developing severe hypertension by 50%. The risk of PE and PU was similar in AHT-treated and placebo-treated patients. The risk of infant death was unaffected by AHT treatment. Using different AHTs did not affect the risk of maternal or infant outcomes. A combination of beta-blockers and calcium channel blockers was 30% more effective than methyldopa in lowering the risk of severe hypertension.   

The authors concluded that AHTs may prevent severe hypertension during pregnancy.   

The authors comment that there is insufficient data to draw conclusions on some outcomes. Larger trials are needed to confirm the usefulness of AHT treatment for MMH in pregnancy. 

If you have any concerns regarding hypertension during pregnancy, please consult with your doctor.